Sewing machine and process for sewing together, by means of said sewing machine, at least two overlapping flaps of textile

ABSTRACT

A sewing machine of an “overlook” “cut-and-sew” type for sewing together at least two flaps ( 3   a   , 3   b ) of textile that are overlapping and belonging to one or more textile articles, comprising at least a needle plate ( 2 ) suitable for supporting at least two overlapping flaps ( 3   a   , 3   b ) of textile of one or more textile articles which are sliding for forming sewing stitches ( 10   a   , 10   b   , 10   c ), the needle plate ( 2 ) being provided with through-openings defining respective seatings ( 4 ) for passage of sewing needles ( 5 ) and at least a lateral appendage ( 6 ) defining a sliding line ( 7 ) for the sewing stitches ( 10   a   , 10   b   , 10   c ); a lower crochet hook ( 14 ); an upper crochet hook ( 15 ); and at least a sewing needle bearing device ( 11 ) with at least three sewing needles ( 5 ) mounted on the device ( 11 ), reciprocally flanked, aligned to one another and supplied with respective sewing threads ( 10 ), and being suitable for passing through the seatings ( 4 ) of the needle plate ( 2 ) for sewing the over-lapping flaps ( 3   a   , 3   b ) of textile, the needle plate ( 2 ) being provided with at least three of the seatings ( 4 ) for passage of the sewing needles ( 5 ), each of the seatings ( 4 ) for passage of the sewing needles ( 5 ) being configured for being crossed by at least a respective sewing needle, the needle plate ( 2 ) being provided with respective separating portions ( 8 ) suitable for at least partially separating each seating for passage of sewing needles ( 5 ) from the adjacent seatings ( 4 ) for passage of needles ( 5 ), at least at the passage zone ( 9 ) of the needles ( 5 ), such as to enable formation in parallel of at least three sewing stitches ( 10   a   , 10   b   , 10   c ) that are distinct and reciprocally distanced from one another.

The present invention relates to a sewing machine of the “overlock” “cut-and-sew” type for sewing together at least two superposed flaps of textile and belonging to one or more textile articles. The invention further relates to a process for sewing together at least two superposed flaps of textile by means of a sewing machine of the overlock cut-and-sew type.

The “overlock” “cut-and-sew” sewing machine can be for example a machine of the type products by UNION SPECIAL® in one of the models from the 9M series, or the like, as described for example in the relative instruction manual and catalog, 103XQA-GR, of November 2006.

The type of stitch known as overlock or also as overedge is in itself widely known in the sector and will therefore not be described in further detail in the present description. As is known, this type of sewing machine can be used for numerous applications, among which also the sewing of light-textile articles such as ladies' tights, and the like. These sewing machines are in particular applicable as components of known machines for assembling textile articles automatically, in which a plurality of articles are assembled to one another (for example the assembling of two tubular stocking legs to form a single textile article known as panty-hose).

In the field of these assembly machines of textile articles, sewing machines of the overlock cut-and-sew type completely automatically perform the cutting of at least two flaps of textile, by moving appropriate sewing needles and elements of known type known as “crotchets”, without any intervention by an operator.

It is known that the type of sewing realised by sewing machines of the overlock cut-and-sew type, in which two flaps of textiles are sewn superposed on one another, can in some cases exhibit an excessive thickness for an optimal use of the product, and thus can be aesthetically unattractive and uncomfortable for the wearer of the product.

An example of this known type of sewing machine is described in patent U.S. Pat. No. 3,079,882A (Washburn) which illustrates a sewing machine of the overedge type with a specific needle plate and two sewing needs and the content of which, relatively to the description of the formation of the sewing stitches is to be considered incorporated in the present text, for reference.

The two-stitch sewing realised by this machine enables effective sewing of the two flaps of the textile, but is excessively thick for some particular applications, for example for sewing tights and in general light textiles, with respect to which the presence of the stitching in relief can be annoying.

A further example of a sewing machine of the overedge type is illustrated in patent U.S. Pat. No. 3,885,509A (Cox), which describes a machine provided with three sewing needles cooperating with a needle plate having two passage seatings for the needles, so that a first needle passes in the relative seating, and the remaining two needles pass in another common seating. This solution is proposed in the attempt to obtain a stitching that is less thick and equally efficient, but the result is only partially satisfying.

A third solution that has been proposed is illustrated in patent U.S. Pat. No. 6,167,825 (Marchetti), in which the sewing machine of the overlock type is equipped with two sewing needles and with a needle plate having a lateral appendage having a first portion with substantially parallel sides and a second portion which narrows. The contents of the patent, relatively to the description of the structure of the textile machine and the forming of the sewing stitches, is to be considered as incorporated in the present text for reference.

Such solution was aimed at enabling obtaining an “overlock” stitching which might thereafter be better stretched out, better separating the two sewn flaps of textile, and therefore having a less thick seam. This solution too is not without drawbacks, as the presence of the first parallel position can obstruct the sliding of the sewing stitches and as the conformation of the needle plate illustrated in the patent determines a stitching that is not very tight at the point of join of the two textile flaps, with the risk, especially in the case of light textiles, of an opening appearing in the stitching at some points, with aesthetic and functional drawbacks.

The aim of the present invention is to obviate one or more of the above-described drawbacks.

An aim of the invention is to provide a sewing machine of an overlock cut-and-sew type which enables sewing together at least two flaps of textile that are overlapping and belonging to one or more textile articles, such as to realise textile articles of high quality and substantially free of imperfections.

A further aim of the invention is to provide a sewing machine of an overlock cut-and-sew type which enables reducing production waste.

A further aim of the invention is to provide a sewing machine of an overlock cut-and-sew type which enables obtaining sewing of a high quality and perfectly “closed” at the joining point between the two flaps of textile.

A further aim of the invention is to provide a sewing machine of an overlock cut-and-sew type which enables obtaining stitched seams which are controlledly extendable to achieve a sewing effect that is wider and/or flatter with respect to known stitched seams.

A further aim of the invention is to provide a sewing machine of an overlock cut-and-sew type which enables obtaining products having a high degree of uniformity within the range of the various articles produced.

A further aim of the invention is to provide a sewing machine of an overlock cut-and-sew type which enables obtaining stitched seams simply, rapidly and automatically, in particular also integrating the sewing machine in an automatic machine for assembly of textile articles.

A further aim of the invention is to provide a sewing machine of an overlock cut-and-sew type which is simple, sturdy and economical to manufacture, also in terms of modest modifications with respect to the sewing machines of known type.

These and other aims besides, which will better emerge during the course of the following description, are substantially attained by a sewing of an overlock cut-and-sew type, and a process for use thereof, according to the appended claims, in any combination with one another and/or with one or more of the aspects indicated herein below.

In an aspect, taken alone or in combination with any one of the claims or aspects indicated in the following, the invention further relates to a sewing machine, according to any one of the appended claims or indicated aspects, in which the upper crochet is supplied with the tying thread and the lower crochet is not supplied with the tying thread and is therefore “blind”, or wherein the lower crochet is supplied with the tying thread and the upper crochet is not supplied with the tying thread and is therefore “blind”, or wherein both the upper and lower crochets are supplied with the tying thread.

In a further aspect, taken alone or in combination with any one of the claims or aspects indicated in the following, the invention further relates to a sewing machine, according to any one of the appended claims or indicated aspects, wherein at least one of the seatings for passage of sewing needles is dimensioned and configured for the passage of two adjacent sewing needles.

In a further aspect, taken alone or in combination with any one of the claims or aspects indicated in the following, the invention further relates to a sewing machine, according to any one of the appended claims or indicated aspects, comprising at least two separating portions or wherein the separating portions each exhibit a thickness of at least 0.6 mm or at least 0.8 mm or at least 1 mm.

In a further aspect, taken alone or in combination with any one of the claims or aspects indicated in the following, the invention further relates to a sewing machine, according to any one of the appended claims or indicated aspects, wherein the separating portions exhibit a longitudinal extension along an advancement direction of the flaps of textile of at least 0.5 cm, or at least 1 cm, or at least 1.5 cm.

In a further aspect, taken alone or in combination with any one of the claims or aspects indicated in the following, the invention further relates to a sewing machine, according to any one of the appended claims or indicated aspects, wherein the needle plate is made of a metal material and wherein the openings defining the seatings are realised by slot-milling of the needle plate.

In a further aspect, taken alone or in combination with any one of the claims or aspects indicated in the following, the invention further relates to a sewing machine, according to any one of the appended claims or indicated aspects, wherein the separating portions are defined by separating elements mounted on the needle plate at the corresponding mounting seatings.

In a further aspect, taken alone or in combination with any one of the claims or aspects indicated in the following, the invention further relates to a sewing machine, according to any one of the appended claims or indicated aspects, wherein the sliding line of the lateral appendage exhibits, at least in a tract extending between the passage zone of the sewing needles and an end portion of the appendage, or over a whole extension thereof, a conformation which is substantially curved and transversal with respect to a prevalent longitudinal development direction of the lateral appendage and/or to the sliding direction of said flaps of textile.

In a further aspect, taken alone or in combination with any one of the claims or aspects indicated in the following, the invention further relates to a sewing machine, according to any one of the appended claims or indicated aspects, wherein the substantially curved conformation is substantially concave or wherein the substantially curved conformation is substantially convex.

In a further aspect, taken alone or in combination with any one of the claims or aspects indicated in the following, the invention further relates to a sewing machine, according to any one of the appended claims or indicated aspects, wherein the stretching device of the tying thread from the upper crotchet and/or the lower crotchet is a stretcher blade oscillating in synchrony with the sewing needle-bearing device.

In a further aspect, taken alone or in combination with any one of the claims or aspects indicated in the following, the invention further relates to a sewing machine, according to any one of the appended claims or indicated aspects, wherein the sewing machine is automatic and/or integrated in a machine for assembling textile articles.

In a further aspect, taken alone or in combination with any one of the claims or aspects indicated in the following, the invention further relates to a sewing machine, according to any one of the appended claims or indicated aspects, wherein the needle thread feeder and the tying thread feeder are of an active type, able to actively supply the thread to the needles or the crotchets or wherein the needle thread feeder and the tying thread feeder are passive and able to passively supply the thread which is pulled directly by the needles or crochets.

In a further aspect, the invention further relates to a needle plate according to the characteristics indicated in any one of the claims or aspects indicated in the following.

In a further aspect, the invention further relates to a needle-bearing device according to the characteristics indicated in any one of the claims or aspects indicated in the following.

In a further aspect, the invention further relates to a sewing device of the overlock cut-and-sew type, comprising at least a needle plate and at least three sewing needles, according to the characteristics denoted in any one of the claims or aspects indicated herein below.

In a further aspect, the invention further relates to a machine for assembling textile articles comprising a sewing machine according to any one of the appended claims or the aspects indicated herein.

In a further aspect, the invention further relates to equipment for a sewing machine of an overlock cut-and-sew type for sewing together at least two flaps of textile that are overlapping and belonging to one or more textile articles, the equipment comprising at least a needle plate suitable for supporting at least two overlapping flaps of textile of one or more textile articles which are sliding for forming sewing stitches, the needle plate being provided with through-openings defining respective seatings for passage of sewing needles and at least a lateral appendage defining a sliding line for the sewing stitches; and further comprising at least a sewing needle-bearing device, provided with three sewing needles mounted on said sewing needle-bearing device, reciprocally flanked, aligned to one another and supplied with respective sewing threads, the sewing needles being suitable for passing through the seatings of the needle plate for sewing the overlapping flaps of textile, the needle plate being provided with at least three of said seatings for passage of the sewing needles, each of the seatings for passage of the sewing needles being configured for being crossed by at least a respective sewing needle, the needle plate being provided with respective separating portions suitable for at least partially separating each seating for passage of sewing needles from the adjacent seatings for passage of needles, at least at the passage zone of the needles, such as to enable formation in parallel of at least three sewing stitches that are distinct and reciprocally distanced from one another.

Further characteristics and advantages will more fully emerge from the detailed description of a preferred but not exclusive embodiment, according to the accompanying figures of the drawings, in which:

FIG. 1 is a perspective view of some components of a sewing machine according to an embodiment of the present invention;

FIG. 2 is a perspective view of some components of a sewing machine according to an embodiment of the present invention;

FIG. 3 is a larger-scale view of a component of FIG. 1, in particular a needle-bearing device;

FIG. 4 is a larger-scale view of a component of FIG. 1, in particular a lower crotchet;

FIG. 5 is a larger-scale view from above of a component of FIG. 1, in particular a needle plate;

FIG. 6 is a detail of the sewing machine of FIG. 1 relating to a forming step of the sewing stitches, with a needle plate sectioned for the sake of clarity;

FIG. 7 is a view from above of a forming step of sewing stitches on two flaps of textile, at the needle plate of FIG. 5;

FIG. 8 is a front view in section of the needle plate of FIG. 7, with the sewing stitches illustrated, realised at the needle plate;

FIG. 9 is a plan view of two flaps of textile sewn with a process according to an embodiment of the present invention, as illustrated in FIG. 7, in which the textiles have been partially separated, stretching the stitches sewn;

FIG. 10 is a lateral view of the two flaps of textile of FIG. 9, sewn using a process according to an embodiment of the present invention and partially separated by stretching the stitches sewn.

With reference to the figures, 1 denotes in its entirety a sewing machine of an overlock cut-and-sew type for sewing together at least two flaps 3 a, 3 b of textile that are overlapping and belonging to one or more textile articles.

FIG. 1 illustrates some essential components of the sewing machine 1. The remaining parts of the sewing machine 1 are of known type and therefore are not illustrated in the accompanying drawings and are not described in detail in the present description.

The sewing machine 1 comprises at least a needle plate 2 able to support at least two superposed flaps 3 a, 3 b of textile, of one or more sliding textile articles, for forming sewing stitches.

The needle-bearing plate 2 is provided with through-openings defining respective seatings 4 for the passage of sewing needles 5 and at least a lateral appendage 6 defining a sliding line 7 for the sewing stitches 10 a, 10 b, 10 c.

The needle-bearing plate 2 is provided with at least three seatings 4 for passage of sewing needles 5, each of the seatings 4 for passage of sewing needles 5 being configured such as to be crossed by at least a respective sewing needle 5.

The needle-bearing plate 2 is provided with respective separating portions 8 able to at least partly separate each seating for passage of sewing needles 5 from the seatings 4 for the passage of adjacent sewing needles 5, at least at the passage zone 9 of the needles 5, so as to enable forming at least three sewing stitches 10 a, 10 b, 10 c that are distinct and reciprocally distant from one another.

Each of the seatings 4 for the passage of sewing needles 5 can be dimensioned and configured for passage of a single and corresponding sewing needle, as in the embodiment illustrated in the appended drawings. The seatings 4 for the passage of sewing needles 5 can be entirely separate from one another over the whole extension thereof by means of the separating portions 8. The seatings 4 for the passage of sewing needles 5 can be defined by through-openings that are entirely distinct from one another.

The needle plate 2 can comprise at least two separating portions or in which the separating portions 8 each exhibit a thickness of at least 0.6 mm or at least 0.8 mm or at least 1 mm. The separating portions 8 can exhibit a longitudinal extension along an advancement direction of the flaps 3 a, 3 b of textile of at least 0.5 cm, or at least 1 cm or at least 1.5 cm.

The needle plate 2 can be made of a metal material and the openings defining the seatings 4 can be realised by slot-milling of the needle plate 2. Alternatively, for example, the separating portions 8 can be defined by separating elements mounted on the needle plate 2 at corresponding mounting seatings.

In a variant embodiment, not illustrated, at least one of the seatings 4 for sewing needle 5 passage can be dimensioned and configured for enabling passage of two adjacent sewing needles 5, and therefore four needles 5 can be provided, passing in three seatings 4, two needles 5 being passing in a common seating. The sewing machine 1 further comprises at least a sewing needle-bearing device 11, such as for example a needle-bearing bar.

The sewing machine 1 further comprises at least three sewing needles 5 mounted on the sewing needle-bearing 11 device, reciprocally flanked, aligned to one another and supplied with respective sewing threads 10 for needles. The sewing needles 5 are suitable for passing through the seatings 4 of the needle plate 2 for sewing the overlapping flaps 3 a, 3 b of textile.

The needles 5 can be mounted on the needle-bearing device 11 with a reciprocal distance defined by an interaxis comprised between 1.4 e 2.8 mm, or between 1.5 and 2.5 mm or between 1.6 and 2.0 mm, corresponding to the distances between the eyelets 19 of the needles 5 from which the respective sewing threads exit.

The needles 5 can be equi-distanced, being mounted on the needle-bearing device (11) at equal distances between adjacent needles (5).

In a variant which is not illustrated the needles can be mounted with different interaxes between them. The needles can be of a same size and can be supplied with identical threads, or different threads of the same size. Alternatively the needles can exhibit different sizes and be supplied with threads of different sizes.

As can be seen in FIG. 7, the sliding line of the lateral appendage 6 exhibits, at least in a tract extending between the sewing needle 5 passage zone 9 and a front end portion of the appendage 6, or over the whole extension thereof, a substantially straight conformation that is transversal with respect to a prevalent longitudinal direction of the lateral appendage 6 and/or the sliding direction of the flaps 3 a, 3 b of textile.

The lateral appendage 6 can exhibit a front portion 6 a having a narrowed end, having a thickness, measured in a through-plane for an upper rest surface of the needle plate 2, of less than 2 mm or less than 1 mm or less than 0.5 mm.

The lateral appendage 6 can exhibit a rear base portion 6 b, opposite the front end portion, having a transversal thickness at the longitudinal extension comprised between 4 mm and 7 mm, or between 5 mm and 6.5 mm, or between 5.5 e 6 mm.

The lateral appendage 6 can exhibit, at the passage zone 9 of the sewing needles 5, a thickness 6 c transversal to the longitudinal extension, comprised between 3 mm and 6 mm, or between 4 mm and 5.5 mm, or between 4.2 and 5 mm. The transversal thickness can be greater than 3 mm, or greater than 3.5 mm, or greater than 4 mm, or greater than 4.2 mm.

Alternatively the sliding line 7 of the lateral appendage 6 can exhibit, at least in a portion extending between the passage zone 9 of the sewing needles 5 and a terminal end of the appendage 6, or in all the extension thereof, a substantially curved conformation that is transversal with respect to a prevalent longitudinal extension direction of the lateral appendage 6 and/or to the sliding direction of the flaps 3 a, 3 b of textile. The substantially curved conformation can be substantially concave or substantially convex.

As can be seen in FIG. 8, at least the lateral appendage 6 defining a sliding line and/or at least one of the separating portions 8 and/or all the separating portions 8 can be inferiorly terminated or tapered to allow for passage of the lower crochet in proximity of the needle plate 2.

The sewing machine 1 can further comprise an advancing device (not illustrated as of known and conventional type) able to advance the flaps 32 a, 3 b of superposed textile along an advancement direction with respect to the needle plate 2 during a sewing operation.

The sewing machine 1 can further comprise a device 12 for cutting the flaps 3 a, 3 b of superposed textile at a cutting line 20 of the textile, in proximity to and upstream of the lateral appendage 6 along the advancement direction of the flaps 3 a, 3 b of textile, as illustrated in FIG. 7.

The sewing machine 1 can further comprise at least a thread feeder for needles 5 able to supply sewing thread 10 to the needles 5 of the sewing machine.

The sewing machine 1 further comprises at least a lower crochet 14 and at least an upper crochet 15, able to contribute to the forming of the stitches 10 a, 10 b, 10 c.

The sewing machine 1 further comprises at least a tying thread feeder 16 able to supply tying thread to at least from between the upper crochet 15 and the lower crochet 14.

In a first embodiment, illustrated in the figures, the lower crochet 14 is supplied with the tying thread 17 and the upper crochet 15 is not supplied with the tying thread 17 and therefore is of the “blind” type.

In a variant that is not illustrated, the upper crochet 15 can be supplied with the tying thread 17 and the lower crochet 14 can be not supplied with the tying thread 17 and therefore of the “blind” type.

In a further variant, not illustrated, both the upper crochet 15 and the lower crochet can be supplied with the tying thread 17. In the illustrated embodiment, the lower crochet 14, supplied with tying thread 17, contributes to the formation of the sewing stitches 10 a, 10 b, 10 c with the respective tying thread 17 which cooperates with the sewing thread 10, while the upper crochet 15, not supplied, or “blind”, contributes to the forming of the sewing stitches 10 a, 10 b, 10 c by operating on the tying thread 17 supplied by the lower crochet 14.

The sewing machine 1 further comprises a stretcher device 18 of the tying thread 17 from the upper crochet 15 and/or from the lower crochet 14. The stretcher device 18 of the tying thread 17 from the upper crochet 15 and/or from the lower crochet 14 can be for example a stretcher blade oscillating in synchrony with the sewing needle-bearing device 11.

The thread feeder 13 for needles 5 and the thread feeder 16 of tying thread can be of the active type, able to actively supply the thread to the needles 5 or to the crochets, or alternatively the needle thread feeder 13 and the tying thread feeder 16 can be of the passive type and able to passively supply the thread which is pulled directly by the needles 5 or by the crochets.

In a variant that is not illustrated, the sewing machine 1 can comprise four of the sewing needles 5 mounted on the needle-bearing device 11 and the needle plate can be provided with four of the openings for the passage of sewing needles 5.

The invention further relates to an equipment for a sewing machine 1 of the overlock sew-and-cut type, the equipment comprising at least a needle plate 2 and at least three sewing needles 5, such as to enable the formation of at least three sewing stitches 10 a, 10 b, 10 c distinct and reciprocally distanced from one another, as described above.

The equipment essentially comprises the components illustrated in FIG. 1. The sewing machine 1 can be automatic, in particular in the case in which it is integrated in a machine for assembly of the textile articles.

The invention further relates to a machine for assembling textile articles, of known type and thus not described in the present text, comprising a sewing machine 1 of the above-described type. The sewing machine will not be described in greater detail as the remaining parts thereof are conventional and of known type.

The present invention further relates to a process for sewing together at least two superposed flaps 3 a, 3 b of textile with a sewing machine 1 of the overlock cut-and-sew type, comprising at least steps of: providing at least two superposed flaps 3 a, 3 b of textile at a needle plate 2 of a sewing machine 1 of the overlock cut-and-sew type, the needle plate 2 being provided with at least three openings, at least partially distinct from one another, for the passage of sewing needles 5; advancing the flaps 3 a, 3 b of textile with respect to the needle plate 2; progressively cutting a lateral portion of the flaps 3 a, 3 b of textile; causing each of the three openings for the passage of sewing needles 5 to be passed through by at least a respective sewing needle supplied with a respective sewing thread 10, such that the at least three reciprocally-flanked sewing needles 5 sew the flaps 3 a, 3 b of textile to each other, realising at least three distinct sewing stitches 10 a, 10 b, 10 c, cooperating with at least a lower crochet 14 and with at least an upper crochet 15, at least one of the crochets being supplied with a tying thread 17.

Various aspects of the process, corresponding to the further aspects described above in relation to the sewing machine, are not repeated herein.

The further aspects of the forming process of the sewing stitches not described in detail in the present description and not deriving from peculiar characteristics of the sewing machine as described above are to be considered of conventional type.

The invention as it is conceived is susceptible to numerous modifications and variants, all falling within the scope of the inventive concept, and the cited components can be substituted by other technically-equivalent elements.

The invention provides important advantages

Primarily the invention enables obviating at least some of the drawbacks of the prior art.

The invention further enables sewing together at least two superposed flaps of textile belonging to one or more textile articles, realising textile articles of high quality and substantially free of imperfections.

The invention further enables obtaining high-quality and perfectly “closed” seams in the join points between the two flaps of textile and/or reducing production waste.

The invention further enables obtaining seams that are extendable in a controlled way such as to provide a wider stitching effect and/or a flatter stitching effect with respect to the known stitching.

The invention further enables obtaining productions with high levels of uniformity between the various articles produced.

The invention further enables realising stitching simply, rapidly and automatically, in particular also by integrating the sewing machine in an automatic machine for assembling textile articles of known type.

The invention is also simple, sturdy and relatively economical to manufacture, and guarantees high standards of repeatability and safety. 

1. A sewing machine of an overlock cut-and-sew type for sewing together at least two flaps (3 a, 3 b) of textile that are overlapping and belonging to one or more textile articles, comprising at least: a needle plate (2) suitable for supporting at least two overlapping flaps (3 a, 3 b) of textile of one or more textile articles which are sliding for forming sewing stitches (10 a, 10 b, 10 c), the needle plate (2) being provided with through-openings defining respective seatings (4) for passage of sewing needles (5) and of at least a lateral appendage (6) defining a sliding line (7) for the sewing stitches (10 a, 10 b, 10 c); a lower crochet hook (14); an upper crochet hook (15); an advancing device suitable for advancing said overlapping flaps (3 a, 3 b) of textile along an advancement direction with respect to said needle plate (2) during a sewing operation; a device (12) for cutting said overlapping flaps (3 a, 3 b) of textile in correspondence of a cutting line (20) of the textile, in proximity and upstream of said lateral appendage (6) along said advancement direction of said flaps (3 a, 3 b) of textile; at least a thread feeder (13) for needles suitable for supplying sewing thread (10) to the needles (5) of said sewing machine; at least a tying thread feeder (16) for supplying tying thread (17) to at least one from between said upper crochet (15) and said lower crochet (14); a stretcher device (18) of the tying thread (17) from said upper crochet (15) and/or said lower crochet (14); at least a sewing needle-bearing device (11); characterised in that it comprises at least three sewing needles (5) mounted on said sewing needle-bearing (11) device, reciprocally flanked, aligned to one another and supplied with respective sewing threads (10), said sewing needles (5) being suitable for passing through said seatings (4) of the needle plate (2) for sewing the overlapping flaps (3 a, 3 b) of textile, said needle plate (2) being provided with at least three of said seatings (4) for passage of the sewing needles (5), each of said seatings (4) for passage of the sewing needles (5) being configured for being crossed by at least a respective sewing needle, the needle plate (2) being provided with respective separating portions (8) suitable for at least partially separating each seating for passage of sewing needles (5) from the adjacent seatings (4) for passage of needles (5), at least at the passage zone (9) of the needles (5), such as to enable formation in parallel of at least three sewing stitches (10 a, 10 b, 10 c) that are distinct and reciprocally distanced from one another.
 2. The sewing machine of claim 1, characterised in that each of said seatings (4) for passage of sewing needles (5) is dimensioned and configured for the passage of a single and corresponding sewing needle.
 3. The sewing machine of claim 1, characterised in that said seatings (4) for passage of sewing needles (5) are entirely separated from one another over their whole extension by means of said separating portions (8) and/or are defined by through-openings that are completely distinct from one another.
 4. The sewing machine of claim 1, characterised in that said needles (5) are mounted on the needle-bearing device (11) at a reciprocal distance defined by an interaxis comprised between 1.4 and 2.8 mm, or between 1.5 and 2.5 mm or between 1.6 and 2.0 mm and/or wherein said needles (5) are reciprocally equidistanced, being mounted on the needle-bearing device (11) at equal distances between adjacent needles (5).
 5. The sewing machine of claim 1, wherein at least said lateral appendage (6) defining a sliding line (7) and/or at least one of said separating portions (8) and/or all said separating portions (8) are inferiorly terminated or tapered for enabling the passage of said lower crochet (14) in proximity of said needle plate (2).
 6. The sewing machine of claim 1, wherein said sliding line (7) of said lateral appendage (6) exhibits, at least in a tract extending between the passage zone (9) of the sewing needles (5) and a front end portion of the appendage (6), or over a whole extension thereof, a conformation which is substantially straight and transversal with respect to a prevalent longitudinal development direction of the lateral appendage (6) and/or to the sliding direction of said flaps (3 a, 3 b) of textile.
 7. The sewing machine of claim 1, wherein said lateral appendage (6) exhibits a front portion having a narrowed end, having a thickness measured in a plane passing through an upper rest surface of said needle plate (2) of less than 2 mm or 1 mm or 0.5 mm, and a rear base portion, opposite the front end portion, having a thickness, transversal to its longitudinal extension, comprised between 4 mm and 7 mm, or between 5 mm and 6.5 mm, or between 5.5 and 6 mm.
 8. The sewing machine of claim 1, wherein said lateral appendage (6) exhibits, at said passage zone (9) of the sewing needles (5), a thickness transversal to its longitudinal extension that is comprised between 3 mm and 6 mm, or between 4 mm and 5.5 mm, or between 4.2 and 5 mm, or wherein said transversal thickness is greater than 3 mm, or greater than 3.5 mm, or greater than 4 mm, or greater than 4.2 mm.
 9. The sewing machine of claim 1, wherein four of said sewing needles (5) are comprised, mounted on the needle-bearing device (11) and wherein said needle plate (2) is provided with four of said openings for the passage of sewing needles (5).
 10. A process for sewing at least two overlapping flaps (3 a, 3 b) of textile together, by means of an overlock cut-and-sew sewing machine (1), comprising at least steps of: arranging at least two overlapping flaps (3 a,3 b) of textile in correspondence of a needle plate (2) of a sewing machine (1) of the overlock cut and sew type, the needle plate (2) being provided with at least three openings, at least partially distinct from one another, for passage of sewing needles (5); advancing said flaps (3 a, 3 b) of textile with respect to said needle plate (2); progressively cutting a lateral portion of the flaps (3 a, 3 b) of textile; passing at least a respective sewing needle, fed with a respective sewing thread (10), through each of the three openings for the passage of sewing needles (5), such that the at least three reciprocally-flanked sewing needles (5) sew said flaps (3 a, 3 b) of textile one to the other realising at least three distinct sewing stitches (10 a, 10 b, 10 c), cooperating with at least a lower crochet (14) and at least an upper crochet (15), at least one of the crochets being fed with a tying thread (17). 